--- title: "Node.js Modern Batteries-Included Built-ins" description: "Between Node.js v20 and v26 (2024-2026) the runtime absorbed a wave of capabilities that" --- # Node.js Modern Batteries-Included Built-ins ## Overview Between Node.js v20 and v26 (2024-2026) the runtime absorbed a wave of capabilities that historically required an npm dependency. A SQLite driver, a WebSocket *client*, `.env` parsing, a task runner, file watching, glob matching, terminal colors, deep cloning, and a V8 startup cache now all ship in core. The practical upshot: many small projects can drop `better-sqlite3`, `ws`, `dotenv`, `nodemon`, `chalk`, `glob`, and `lodash.cloneDeep` entirely. The catch — and the reason this reference exists — is **stability is per-feature and recent**. Some of these are fully Stable (2), several are Release Candidate (1.2), and a few are still Experimental (1) or "Active development" (1.1). Shipping an Experimental API to production without pinning the Node version is the cardinal sin here. Every concept below states its **added-in version and current stability index explicitly**; treat those as the load-bearing facts, because an API that is RC today may change a method signature in the next minor. Scope boundaries (owned by sibling references in this family): Single-Executable Applications, the `--permission` model, and native TypeScript stripping live in `nodejs-typescript-and-runtime-features`; the **deep** `node:test` runner (mocking, coverage, reporters, snapshots) lives in `nodejs-test-runner` — `node:test` is mentioned here only as "it exists, it replaces Jest/Mocha for many projects, see the sibling"; Bun/Deno/edge equivalents live in `javascript-runtimes-deno-bun-edge`. A note on reading stability: index **2** = Stable; **1.2** = Release Candidate (API frozen, shipping unflagged, final polish); **1.1** = Active development (unflagged but may change); **1** = Experimental; **1.0** = Early development. Anything below 2 deserves a pinned `engines.node` and a changelog read on upgrade. ## Core concepts ### 1. `node:sqlite` — a built-in synchronous SQLite driver Added in **v22.5.0**, unflagged since **v23.4.0 / v22.13.0** (was behind `--experimental-sqlite`), currently **Stability 1.2 - Release Candidate**. Available only under the `node:` scheme. It is the in-core analogue of **`better-sqlite3`**: synchronous, prepared-statement-centric, fast. ```js import { DatabaseSync } from 'node:sqlite'; const db = new DatabaseSync(':memory:'); // or a path, or a Buffer/URL db.exec('CREATE TABLE users(id INTEGER PRIMARY KEY, name TEXT) STRICT'); const insert = db.prepare('INSERT INTO users (id, name) VALUES (?, ?)'); insert.run(1, 'Ada'); // { changes: 1, lastInsertRowid: 1 } const byId = db.prepare('SELECT * FROM users WHERE id = ?'); byId.get(1); // { id: 1, name: 'Ada' } | undefined db.prepare('SELECT * FROM users').all(); // [{ id, name }, ...] for (const row of byId.iterate(1)) { /* streaming */ } // iterate added v23.4.0/v22.13.0 ``` - **`DatabaseSync(path[, options])`** options: `open` (default `true`), `readOnly`, `enableForeignKeyConstraints` (default `true`), `allowExtension`, `timeout` (busy timeout ms), `readBigInts`, `returnArrays`, `allowBareNamedParameters` (default `true`), `allowUnknownNamedParameters`. `:memory:` is an in-memory DB. - **`StatementSync`** (from `db.prepare(sql)`): `get()` → first row or `undefined`; `all()` → array; `run()` → `{ changes, lastInsertRowid }`; `iterate()` → row iterator. Config methods: `setReadBigInts(true)` (read `INTEGER` as `BigInt`), `setReturnArrays(true)`, `setAllowBareNamedParameters(true)`, `setAllowUnknownNamedParameters(true)`. Introspection: `columns()`, `sourceSQL`, `expandedSQL`. - **Parameter binding** — three styles: anonymous `?` (positional varargs), and named `:name` / `@name` / `$name` (pass an object keyed by the prefixed name, e.g. `{ ':id': 1 }`; bare keys `{ id: 1 }` work when `allowBareNamedParameters` is on). - **`db.aggregate(name, { start, step, result, inverse })`** registers custom SQL aggregate / window functions; **`backup(sourceDb, destPath, { rate, progress })`** does an online backup; `db.loadExtension()` requires `allowExtension: true`. `constants` (v23.5.0) exposes `SQLITE_CHANGESET_*`, authorizer codes, etc. (serialize/deserialize landed later, ~v26). - **Type map**: `NULL↔null`, `INTEGER↔number|bigint`, `REAL↔number`, `TEXT↔string`, `BLOB↔Uint8Array`/TypedArray. ### 2. The global `WebSocket` client (undici-backed) A spec-compliant, browser-compatible **`WebSocket`** is exposed on the global scope, backed by undici. Timeline: experimental behind `--experimental-websocket` in **v21**, **on by default in v22.0.0** (disable with `--no-experimental-websocket`), and **no longer experimental as of v22.4.0**. No import needed. ```js const ws = new WebSocket('wss://example.com/feed'); ws.addEventListener('open', () => ws.send('hello')); ws.addEventListener('message', (e) => console.log(e.data)); ws.addEventListener('error', (e) => console.error(e)); ws.addEventListener('close', () => {}); ``` It replaces the **`ws`** package **for client use only**. Critically, there is **no built-in WebSocket *server*** — to accept connections you still need `ws` (or another library). The API is the WHATWG/browser `WebSocket`, not the `ws` EventEmitter API, so it is portable to browsers but is *not* a drop-in for `ws`'s `.on('message')` server-side idioms. ### 3. Environment files — `--env-file`, `loadEnvFile()`, `util.parseEnv()` The in-core replacement for **`dotenv`**. Three surfaces: - **`--env-file=.env`** (CLI) — added **v20.6.0**, **Stable** since **v24.10.0 / v22.21.0**. Loads the file into `process.env` before the app runs; Node-config vars like `NODE_OPTIONS` are honored. Multiple `--env-file` flags stack (later overrides earlier). Real `process.env` values take precedence over file values. **Throws if the file is missing.** - **`--env-file-if-exists=.env`** — added **v22.9.0**. Identical, but silently no-ops if the file is absent (use for optional local overrides). - **`process.loadEnvFile([path])`** — programmatic load (defaults to `./.env`), added v20.12.0/v21.7.0. **`util.parseEnv(content)`** (added **v21.6.0 / v20.12.0**) parses a `.env`-format **string** and returns a plain object without mutating `process.env`. **`.env` parsing rules**: `KEY=value` per line; text after `#` is a comment; values may be quoted with `` ` ``, `"`, or `'` (quotes stripped); **multi-line** quoted values supported (v21.7.0/v20.12.0); a leading `export ` is ignored. **There is NO variable expansion** — `PASSWORD=${SECRET}` is the literal string `${SECRET}`, unlike `dotenv-expand`. This is the single most common migration surprise. ### 4. Task running (`node --run`) and watch mode (`--watch`) **`node --run